Mexican leftist presidential front-runner Andres Manuel Lopez Obrador's lead narrowed for the first time in months as his nearest rival rebounded from corruption allegations ahead of the July 1 election, according to a poll released on Thursday.

Less than two months before Mexicans vote, Lopez Obrador's support grew to 39 percent from 38 percent in the previous poll at the end of March, according to polling firm Parametria, but his lead narrowed to 14 points from 18.

The possibility of a victory by Lopez Obrador, who has threatened changes to the country's landmark reform to lure private investment to its energy markets, has spooked some investors, helping send the peso currency down more than 3 percent in April.

Support for Ricardo Anaya, the candidate of the "For Mexico in Front" coalition of three parties from the right and left, grew to 25 percent from 20 percent the month before. In a recent TV debate, he portrayed himself as the only alternative to the front-runner.

Third-place ruling party candidate Jose Antonio Meade's support fell to 14 percent in the latest poll from 16 percent previously.